<template>
  <view>
    <my-search @search="goToSearch"></my-search>
    <view class="scroll-view-box">
      <!-- 左侧的滑动区域 -->
      <scroll-view class="left-scroll-view" scroll-y="true" :style="{height: wh+'px'}" >
        <block v-for="(item,i) in cateList" :key="i">
          <view :class="['left-scroll-view-item',i===active?'active':'']" @click="activeChange(i)">{{item.cat_name}}</view>
        </block>
      </scroll-view>
      <!-- 右侧的滑动区域 -->
      <scroll-view scroll-y="true" :style="{height: wh+'px'}" :scroll-top="scrollTop">
        <view class="cate-lv2" v-for="(item2,i2) in cateLevel2" :key="i2">
          <view class="cate-lv2-title">
            / {{item2.cat_name}} /
          </view>
          <view class="cate-lv3">
            <view class="cate-lv3-item" v-for="(item3,i3) in item2.children" :key="i3" @click="goToGoodsList(item3)">
              <image :src="item3.cat_icon"></image>
              <text>{{item3.cat_name}}</text>
            </view>
          </view>
        </view>
      </scroll-view>
    </view>
  </view>
</template>

<script>
  export default {
    data() {
      return {
        // 设备的可使用窗口高度
        wh:0,
        //分类数据
        cateList:[],
        //激活状态
        active:0,
        //二级分类
        cateLevel2:[],
        //滚动条位置
        scrollTop:0
      };
    },
    onLoad() {
      const infosys = uni.getSystemInfoSync()
      this.wh = infosys.windowHeight-60
      // console.log(infosys);
      // 获取分类数据
      this.getCateList()
    },
    methods:{
      async getCateList(){
        const {data:res} = await uni.$http.get('/categories')
        if(res.meta.status!==200) return uni.$showMessage()
        this.cateList = res.message
        this.cateLevel2 = res.message[0].children
      },
      activeChange(i){
        this.active = i
        this.cateLevel2 = this.cateList[i].children
        //重置滚动条的位置
        this.scrollTop = this.scrollTop===0?1:0
      },
      goToGoodsList(item3){
        uni.navigateTo({
          url:'/subpkg/good_list/good_list?cid='+item3.cat_id
        })
      },
      goToSearch(){
        uni.navigateTo({
            url:'/subpkg/search/search'
          })
      }
    }
  }
</script>

<style lang="scss">
.scroll-view-box{
  display: flex;
  .left-scroll-view{
    width: 120px;
    .left-scroll-view-item{
      background-color: #F7F7F7;
      line-height: 60px;
      font-size: 12px;
      text-align: center;
      &.active{
        background-color: #FFFFFF;
        position: relative;
        &::before{
          content: '';
          display: block;
          width: 3px;
          height: 30px;
          background-color: #c00000;
          position: absolute;
          top: 50%;
          left: 0;
          transform: translateY(-50%);
        }
      }
    }
  }
  .cate-lv2-title{
    font-size: 12px;
    font-weight: 700;
    text-align: center;
    padding: 15px 0;
  }
}
.cate-lv3{
  display: flex;
  flex-wrap: wrap;
  .cate-lv3-item{
    display: flex;
    flex-direction: column;
    width: 33.33%;
    justify-content: center;
    align-items: center;
    margin-bottom: 10px;
    image{
      width: 60px;
      height: 60px;
    }
  }
}
</style>
